Lymphomatoid papulosis in an HIV-positive man.

Lymphomatoid papulosis (LyP) is a rare cutaneous lymphoproliferative condition characterized by a chronic, recurrent eruption of papules and nodules that undergo spontaneous regression. The disorder is usually clinically benign; with a minority of cases progressing to malignant lymphoma. LyP is divided into two subtypes based on histologic appearance. Type A resembles Hodgkin's disease with up to 20% of large CD30+ lymphocytes. Type B resembles mycosis fungoides showing an infiltrate of CD4+ lymphocytes and scattered CD30+ cells. Clinically LyP often resembles pityriasis lichenoides et varioliformis acuta but has a strikingly different histological appearance. Histologically, LyP resembles lymphoma (anaplastic T-cell or Hodgkin's) but is distinguished by its benign course. Here we present a case of LyP in a severely immune-repressed HIV-positive patient. This patient presented with pruritic papules involving the upper extremities and a CD4+ T-cell count of 4. Histopathologic examination showed a dense superficial dermal infiltrate comprising normal-sized lymphocytes admixed with larger lymphocytes. Immunophenotyping showed most of the lymphocytes to be CD3+ (T cells). The scattered larger cells were CD30+. The smaller lymphocytes were CD8+ rather than CD4+ as expected for non-HIV-appointed LyP. This may be because of the immune disregulation of HIV disease and the absolute and relative paucity of CD4+ T cells relative to CD8+ T cells.